A week from now, Smashburger-founder Tom Ryan will be elbow-deep in turkey necks.

It takes him two days to make the gravy that he will ladle on the turkey, the potatoes, the stuffing and sides. And before he roasts the turkey and uses stock to deglaze the roasting pan and scrape up the drippings, before he makes a roux to thicken the sauce, he deals with necks, which he finds at Denver butcher shops, including the meat departments at King Soopers stores.

Tom Ryan stuffs his bird, but if you prefer to bake the stuffing separately, his recipe makes enough for two 2-quart casseroles, or 1 large turkey. (Cyrus McCrimmon, The Denver Post)

At least one day before his High Holiday, Ryan dusts the necks with poultry seasoning, salt and pepper, cooks them until they are as dark as chocolate, plops them in a pot of boiling stock and keeps them there for hours, until the meat turns tender. He calls necks the “oxtails of the poultry world,” for their ability to add deep flavor to dishes.

By the time people begin piling their plates on the big day, the Ryan household is nearly swimming in gravy — much more than needed for the feast.

“We deliver gravy as gifts,” said Ryan on a recent Saturday, as he tore meat from necks, to be used in the gravy and stuffing. “It’s coveted.”

I tasted the stuff, and let me tell you — it’s so good, I think he should open a restaurant called Gravy Train; everything gets shellacked with the turkey elixir.

Don’t think he won’t consider it. In addition to the fast-growing Smashburger, Ryan’s company in the past year has launched Live Basil Pizza, a fast-casual pizza chain, and Tom’s Urban 24, an upscale diner on Larimer Square that soon will open locations in Los Angeles and Las Vegas.

That and more keeps Ryan busy, but the corporate toil gets buried and forgotten during Thanksgiving. The holiday is such a big deal in Ryan’s family that it goes by another name: Tomsgiving. If one of his three kids can’t make the feast — last year, a daughter in college was traveling — they force the patriarch to put on a repeat performance. This year, the same daughter is living in Australia, and will miss Turkey Day, so Ryan will make the feast all over again when she comes home for Christmas.

This is not a problem.

“I love this. It’s a passion. A food fest,” he said, while preparing the food for our photos in his grand old Denver home. “It’s a celebration of family, of great food.”

It’s taken 30 years of messing with different recipes to come up with the Ryan standards. While he plays with exotic flavors in his restaurants, none of them even whisper on Thanksgiving.

“We are not into chipotle this, and sriracha that,” said the native Michigander. “This is a Midwest, traditional Thanksgiving.”

Gravy is a Tomsgiving star, but still, it’s part of a cast. And the other players have big roles, too.

Take the turkey, which he calls “turkosaurus.” It’s big. His birds usually run between 30 and 32 pounds. One year, in Chicago, he scored a 42-pound turkey, and they called that holiday SlothFest 2000. One rule: Everybody had to eat in their pajamas.

For the drama, he goes for big birds, which he brines before roasting. But the larger turkeys have benefits beyond the visual punch: Because they take longer to roast, the drippings have more time to turn dark and crunchy and become what Ryan calls “turkey candy.”

His stuffing is perfumed with herbs, like most variations. But in addition to the bird cavity, he packs the neck chamber with cubes of seasoned bread, and it emerges different; mushy and dense, rather than fluffy. Ryan prefers the neck stuffing; his wife, Jody, likes the fluffy version.

Instead of cranberries, he uses raspberries and apples to make a sauce that pairs well with the rest of the meal.

For the grand finale, the yams with praline slink across the stage, and, after the first bites are taken and the gasps emerge, it’s time for the standing ovation. The praline topping — cream, brown sugar, bourbon, vanilla, pecans — turns the dish into something extraordinary. Cover the puréed yams in the gooey goodness, bake it for nearly an hour, serve. Best yam dish I’ve ever tasted.

He and Jody have shared the meal every year since they started dating, in 1987. Two of their kids are in college, and the other followed that job to Australia. During the cooking extravaganza at their home, they both talked about how glad they are for Thanksgiving, how their dedication to the meal has echoed throughout their lives.

“The older we get, the more valuable it gets for us,” said Ryan. “Our kids want to come home and hang out. It’s just lovely.”